Light question .difficulty finding answer

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The discussion revolves around a physics question regarding the conditions under which electrons in a wire emit microwaves with a wavelength of 1.00 mm. The user attempts to solve the problem using relevant equations for speed, frequency, and energy of photons but finds the question poorly worded and unclear. They express confusion about what is meant by "range" in the context of the question. Additionally, there is a request for clarification on the concept of a "short circuit," which leads to a suggestion to start a new thread for that topic. Overall, the main focus is on understanding the physics of microwave emission and the clarity of the question posed by the professor.
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Light question...difficulty finding answer...

My prof. just gave us about 6 questions on the last chapter of the summer semester, which is on light...he said we could try the question but if we couldn't get it right it was okay...I tried it anyways and I cannot get it...

At what range must electrons in a wire vibrate to emmit microwaves with a wavelength of 1.00 mm? He told us to note next to the question the word charge.

So here's what I did...

I used the equation : speed of light in a vacuum = (wavelength)(frequency)
since I was trying to find f I used the equation f= c/Lambda

f= 3.00 x 1068 m/s
______________
1 x 10 ^ -3 m

= 3 X10 ^11 hz

Then I used the equation e=hf to find the enerty of photon

(6.63 X10 ^-3 Js)(3 X 10 ^11 xs)
= 1.98 x10^-22 J

I'm not sure what the question is asking for really...
 
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The question is poorly worded. At what range of what ?

The frequency of emitted radiation depends on the acceleration of the charge, and the relation is quite hard to derive for someone who is not a physics grad. Perhaps all he wants is f = 3* 10^11 Hz ! I don't see the possibility of getting a range of answers unless one of the conditions imposed is in the form of a range itself. This is true of the acceleration of a harmonically oscillating charge, but that would certainly be beyond the scope of your class.
 
General Physics help: Someone explain what a "Short circuit" is?

I am currently reading electricity and although I have read my textbooks well, I still don't understand what a "short circuit" is..thanks
 
hoxlay said:
I am currently reading electricity and although I have read my textbooks well, I still don't understand what a "short circuit" is..thanks

Please don't do this! Start your own thread!
 
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